The team used alginate to make materials they call soft dendritic colloids (SDCs). These are particles with hierarchical branches that give them a fuzzy appearance under a microscope and, much like gecko feet, create a large surface area that boosts van der Waals forces and makes the material really sticky. Velev says a single SDC particle can capture more than a thousand polymer particles from a suspension (Adv. Funct. Mater. 2025, DOI: 10.1002/adfm.202423494).